Jump from custom bootloader to application

Hello, I am trying to build  a custom bootloader which is jumping in the application. In order to do this in a first approach, i wrote a Bootloder which jumps as follows:

For the application I changed the VET_TAB_OFFSET to 0x000A0000UL.

In Keil Settings Target I changed the Read/only Memory Areas:

IROM1 : Start 0x80A000 Size 0x60000

In the Target Options I unchecked Use Memory Layout from Target Dialog

For R/O Base I put 0x080A0000

My scatter file for the application:

LR_IROM1 0x080A0000 0x00060000  {    ; load region size_region
  ER_IROM1 0x080A0000 0x00060000  {  ; load address = execution address
   *.o (RESET, +First)
   *(InRoot$$Sections)
   .ANY (+RO)
   .ANY (+XO)
  }
  RW_IRAM1 0x20000000 0x00020000  {  ; RW data
   .ANY (+RW +ZI)
  }
  RW_IRAM2 0x24000000 0x00080000  {
   .ANY (+RW +ZI)
  }
}

LR_IROM2 0x08100000 0x00100000  {
  ER_IROM2 0x08100000 0x00100000  {  ; load address = execution address
   .ANY (+RO)
  }
}

For the Bootloader

; *************************************************************
; *** Scatter-Loading Description File generated by uVision ***
; *************************************************************

LR_IROM1 0x08000000 0x000A0000  {    ; load region size_region
  ER_IROM1 0x08000000 0x00A0000  {  ; load address = execution address
   *.o (RESET, +First)
   *(InRoot$$Sections)
   .ANY (+RO)
   .ANY (+XO)
  }
  RW_IRAM1 0x20000000 0x00020000  {  ; RW data
   .ANY (+RW +ZI)
  }
  RW_IRAM2 0x24000000 0x00080000  {
   .ANY (+RW +ZI)
  }
}

LR_IROM2 0x08100000 0x00100000  {
  ER_IROM2 0x08100000 0x00100000  {  ; load address = execution address
   .ANY (+RO)
  }
}

I use Keil with the MDK Plus Toolchain on the STM32H753.

I do the jump on the bootloader as follows and nothing happens:

void start_app()
{

	uint32_t JumpAddress = *(volatile uint32_t*) (JUMP_ADDR+4);
	void (*jump_to_application)(void)= (void*) JumpAddress;
	
	

	 HAL_RCC_DeInit();
		__disable_irq();
	__set_MSP(*(__IO uint32_t*) JUMP_ADDR);
	// Disable systick timer and reset it to default values
	SysTick->CTRL = 0;
	SysTick->LOAD = 0;
	SysTick->VAL = 0;
	//__disable_irq();
	//__DSB();
	SCB->VTOR = JUMP_ADDR;
	jump_to_application();
}

What could be the reason?